The disclosed embodiments of the present invention relate to compressive sensing (CS), and more particularly, to an electronic device with flexible processing of CS samples.
Wearable sensor devices are increasingly employed in medical monitoring, where high energy efficiency, small form factor, multi-signal sensing capability and wireless communication capability are essential. A typical wireless bio-sensor system consists of bio-sensor nodes (e.g., wearable bio-sensor devices) that transmit information to a data aggregator (e.g., a smartphone) that receives and processes the bio-sensor output data. One restriction imposed on the wearable bio-sensor devices is power consumption. These wearable bio-sensor devices need to operate for a reasonable amount of time to avoid frequent battery replacement/charging. In general, the majority of the power is consumed by a transmit (TX) circuit (particularly, a power amplifier (PA) of the TX circuit). One solution to reduce the power consumption is to reduce the data rate. Compressive sensing (CS) is a signal processing technique that exploits sparsity for commensurate power savings by enabling alias-free sub-Nyquist-rate acquisition. Hence, CS is very appealing to low-power wearable bio-sensor devices. To achieve good compression ratio in CS framework, it is important to find a suitable basis. However, a typical fixed basis such as wavelet-based CS design only gives a compression ratio (CR) of 2-2.5 if the required signal-to-noise ratio (SNR) is 20 dB or above. In addition, a reconstruction algorithm employed by the typical data aggregator (e.g., smartphone) needs to run till full recovery, and early stop due to computational constraints reduces the reconstruction quality significantly. Moreover, the reconstruction algorithm employed by the typical data aggregator (e.g., smartphone) lacks capability to handle different types of impairments.
Thus, there is a need for a flexible bio-sensing system design that provides a high compression ratio for various bio-signal types and is able to handle different types of impairments.